@article{JRAM_1989__393_153090,
     author = {R\"udiger Landes},
     title = {On the existence of weak solutions of perturbated systems with critical growth.},
     journal = {Journal f\"ur die reine und angewandte Mathematik},
     pages = {21--38},
     year = {1989},
     volume = {393},
     zbl = {0664.35027},
     url = {http://geodesic.mathdoc.fr/item/JRAM_1989__393_153090/}
}